﻿Vol. 64.] CHANNEL OF DRIFT AT HITCHIN. 13 



the Hiver Hiz, flows northwards into the valley of the Ivel and so 

 into the Ouse. The waters of the Hiz are still further augmented 

 by the Orton, which rises about a mile south-east of High Down. 

 Like the Hiz, its waters take a north-easterly direction till it joins 

 that river after a course of 2 miles. 



III. Evidence of the Deep Channel in the Dkift. 



Beginning near the water-parting of the Hitchin and Stevenage 

 Gap and proceeding north-westwards, the first evidence of a deep 

 channel in the Drift is found in the Langley-Ippollitts Valley at 

 Langley Bottom. Here, near the base of the western slope, at a 

 height of 326 feet O.D., are two wells both of which touch the 

 Chalk. They are on opposite sides of the main road to London, that 

 on the eastern side being slightly deeper than that on the western. 

 The occupier of the house on the eastern side has lived there for 

 80 years, and has seen his well cleared out and deepened. He tells 

 me that his well passes through 75 feet of sand and gravel before 

 reaching Chalk, the depth being about 80 feet. 



Chalk comes to the surface in the fields about 300 yards west of 

 the well, and there are numerous chalk-pits in the locality. To the 

 east the surface shows gravel and sand. 



About 650 yards due east of the last well, at a corresponding 

 point on the other side of the valley, but actually in the floor of it, 

 and close to the water-course of the valley-drainage, is Dye's Farm, 

 302 feet O.D. The well here, once shallow, was deepened about 

 three years ago. Mr. John Shilcock, the agent of the estate, kindly 

 furnishes me with the following details : — 



Feet. 



Original depth of the well— soil, red loam 24 



Deepening. 



Sand and ballast (gravel) 18 



Blue clay with chalk-lumps 22 



Boring. 



Blue clay with chalk-lumps 14 



Chalk — plenty of water as soon as it was touched 2 



80 



The material from the well was still to be seen in May 1907. 

 The clay at the bottom of the well and in the boring was the blue 

 Boulder-Clay with Chalk-pebbles in it. Bare Chalk occurs in the 

 fields about 250 yards up the eastern flank of the valley, and there 

 are chalk-pits along the ridge. 



Three-quarters of a mile to the north-west a boring was made by 

 Mr. W. Jackson, of Hill End, in a meadow immediately to the east 

 of the London road, and about 200 yards from it. I estimate that 

 the mouth of the boring was just under 300 feet O.D., and was 

 almost in the valley -bottom. The boring was made by Messrs. 



